Status: In Progress

Location

The project occurs in the Coeur d’Alene Lake south of Harrison and in the Coeur d’Alene
River upstream of where it enters the lake.

Background

Coeur d’Alene Lake integrates the physical, chemical and biological processes from its
watershed, all of the upstream waters and contributing lands. Among these influences,
the Lake has received mine waste from upstream sources in the Silver Valley. Pollution
from historic mine waste deposited more than 75 million tons of sediments contaminated
with metals like cadmium, lead, and zinc in the lake. Although pollution sources are
being reduced through upstream cleanup activities, significant amounts of metals and
nutrients continue to enter the lake every year. The nutrients, metals, productivity,
organisms, and interacting processes of Coeur d’Alene Lake have been monitored
continuously since 2003. The water quality monitoring and modeling of Coeur d’Alene Lake
is described by section 4.3 of the Coeur d’Alene Basin Restoration Plan.

Plans

The project will continue monitoring the nutrients, metals, productivity, organisms, and
interacting processes of Coeur d’Alene Lake to: 1) ensure there are no gaps in the
water quality monitoring data, 2) enhance the ability to refine a modeling tool to
predict effects of upstream actions, and 3) manage data to better inform and guide
restoration. The project will also help the Partnership measure and evaluate Coeur
d’Alene Lake’s response to restoration.

Benefits

The project will measure, model, and improve understanding of Coeur d’Alene Lake, and the
lake’s response to events and land use changes. Project data will also inform
restoration projects and cleanup that deal with contaminated sediments.